The US Supreme Court says it will rule on whether to uphold the first federal ban on an abortion procedure.

It will be the first time an abortion case has come before the court since President George W Bush appointed a new conservative judge to the bench.

The case concerns a law passed in 2003 that banned a form of late abortion.

The law was never enacted because an appeals court said it made no exception to protect a pregnant mother's health.

The Bush administration had appealed to the Supreme Court to consider urgently whether the law - which outlaws so-called partial birth abortions - should be upheld.

Mr Bush has called the procedure an "abhorrent practice".

Generally carried out in the second or third trimester, it involves the foetus being forced into the birth canal, before the brain is removed, the skull crushed and the remains removed from the woman's body.

Doctors who use the method say it is the safest available when the mother's health is threatened by conditions such as heart disease, high blood pressure or cancer.

A number of states have already introduced their own bans on the partial-birth procedure, but the federal legislation would outlaw it across the US.

New court

Abortion is one of the country's most polarising issues and the future of a woman's right to terminate a pregnancy has been a subject of much debate in recent months as new appointments have been made to the Supreme Court.

Conservative court nominee Samuel Alito may take a hardline on abortion

The new make-up of the court could affect abortion rulings.

The new chief justice on the court, John Roberts, is a conservative, but since he replaced another conservative, William Rehnquist, that change was not thought likely to affect the court's balance.

However he has since been joined by another conservative Bush appointee, Samuel Alito.

Justice Alito is thought to be more likely to rule against abortion than his predecessor, Justice Sandra Day O'Connor, who often cast the decisive vote backing rights to terminate a pregnancy.

Those opposed to abortion said they were optimistic this new bench would rule in their favour.

"We're hopeful the high court will determine that the national ban is not only proper, but constitutional as well," said Jay Sekulow of the American Center for Law and Justice.

Pro-choice activists expressed concern.

"The Supreme Court's decision to hear this case is a dangerous act of hostility aimed squarely at women's health and safety," said Cecile Richards, president of the Planned Parenthood Federation of America.

The case will be heard in the court's next term, which starts in October.